A customer asked to prepare the file for a building product declaration in Sweden. Therefore I had to study the assessment criteria. They have three levels: Recommended, Accepted and To be Avoided. Besides the usual questions, the following points were remarkable:

• Besides the actual composition, a lot of questions handle about carcinogens, mutagens, reproductive toxins and endocrine disruptors.
• Special attention was given for Lead (Pb) and Arseen (As). Both elements have a past in the glass industry but are today eliminated.
• Also a lot of other substances are mentioned, which have nothing to do with the (cellular) glass business.
• Renewable raw materials and recovered material must be at least 50% for the highest level “recommended”.
• The usual things like energy consumption during production, recycling after use, packing, last production place, … are of course also requested.
• Information about internal electric and magnetic fields is also needed although unimportant for cellular glass. These questions are new in the bussiness.

For cellular glass, I guess that only the foaming agent may possibly become a difficult point for the “recommended” level, which is 0.1% for substances “possibly carcinogenic to humans”. Today, glass is (industrially) foamed with glycerine, carbon black and silicium carbide. Carbon black (as example: PINOSKLO) and silicon carbide (mineral activator for MISAPOR) have both a classification about  cancerogenicity.

• Carbon black is possibly carcinogenic to humans (Group 2B).
• Fibrous SiC is possibly carcinogenic to humans (Group 2B)

Today, no classification can be found for glycerin (glycerol). As a consequence, we expect that glycerin foamed glass (GLAPOR and most glass foam gravel products) will get a level “RECOMMENDED” in Sweden.